diff --git a/README.md b/README.md
index 79ea6af..4168463 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-![alt text](https://repository-images.githubusercontent.com/75949178/d960b700-5c98-11ea-813c-a94432078605 "O2System Security Atom")
+![alt text](https://www.o2system.id/assets/img/covers/cover-o2system-atom-security.png "O2System Security Atom")
 
 [![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/o2system/security/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/o2system/security/?branch=master)
 [![Build Status](https://scrutinizer-ci.com/g/o2system/security/badges/build.png?b=master)](https://scrutinizer-ci.com/g/o2system/security/build-status/master)
@@ -24,7 +24,6 @@ O2System Security is a collection of class libraries to help build security proc
 - Binary
 - Cookie
 - Crypt via PHP's MCrypt and/or OpenSSL extensions
-- Hexadecimal
 
 ### Featured Encoders
 - Base64
@@ -76,4 +75,4 @@ Please kindly submit your [issues at Github](http://github.com/o2system/security
 ### System Requirements
 - PHP 7.2+
 - [Composer](https://getcomposer.org)
-- [O2System Session](https://github.com/o2system/session)
+- [O2System Session](https://github.com/o2system/session)
\ No newline at end of file
diff --git a/composer.json b/composer.json
index cda8f04..0eb77d0 100644
--- a/composer.json
+++ b/composer.json
@@ -43,4 +43,4 @@
       "O2System\\Security\\": "src"
     }
   }
-}
\ No newline at end of file
+}
diff --git a/src/Authentication/JsonWebToken.php b/src/Authentication/JsonWebToken.php
index 454cb8e..aacdbe7 100644
--- a/src/Authentication/JsonWebToken.php
+++ b/src/Authentication/JsonWebToken.php
@@ -191,9 +191,8 @@ public function decode($token, $key = null)
 
                 return false;
             }
-            
             // Check if this token has expired.
-            if (isset($payload->exp) && ($timestamp - $this->leeway) >= strtotime($payload->exp)) {
+            if (isset($payload->exp) && ($timestamp - $this->leeway) >= $payload->exp) {
                 $this->errors[] = 'Expired token';
 
                 return false;
diff --git a/src/Authentication/User.php b/src/Authentication/User.php
index 34f698a..0d12e98 100644
--- a/src/Authentication/User.php
+++ b/src/Authentication/User.php
@@ -16,7 +16,6 @@
 // ------------------------------------------------------------------------
 
 use O2System\Cache\Item;
-use O2System\Spl\DataStructures\SplArrayObject;
 use O2System\Spl\Traits\Collectors\ConfigCollectorTrait;
 use Psr\Cache\CacheItemPoolInterface;
 
@@ -36,13 +35,13 @@ class User
     public function __construct()
     {
         $this->setConfig([
-            'password' => [
+            'password'    => [
                 'algorithm' => PASSWORD_DEFAULT,
-                'options' => [],
+                'options'   => [],
             ],
             'msisdnRegex' => '/^\+[1-9]{1}[0-9]{3,14}$/',
             'maxAttempts' => 5,
-            'sso' => [
+            'sso'         => [
                 'enable' => false,
                 'server' => base_url(),
             ],
@@ -96,8 +95,8 @@ public function passwordRehash($password)
     {
         if (password_needs_rehash(
             $password,
-            $this->config['password']['algorithm'],
-            $this->config['password']['options']
+            $this->config[ 'password' ][ 'algorithm' ],
+            $this->config[ 'password' ][ 'options' ]
         )) {
             return $this->passwordHash($password);
         }
@@ -118,8 +117,8 @@ public function passwordHash($password)
     {
         return password_hash(
             $password,
-            $this->config['password']['algorithm'],
-            $this->config['password']['options']
+            $this->config[ 'password' ][ 'algorithm' ],
+            $this->config[ 'password' ][ 'options' ]
         );
     }
 
@@ -145,7 +144,7 @@ public function passwordVerify($password, $hash)
      */
     public function attempt()
     {
-        $_SESSION['userAttempts'] = $this->getAttempts() + 1;
+        $_SESSION[ 'userAttempts' ] = $this->getAttempts() + 1;
     }
 
     // ------------------------------------------------------------------------
@@ -158,8 +157,8 @@ public function attempt()
     public function getAttempts()
     {
         $currentAttempts = 0;
-        if (isset($_SESSION['userAttempts'])) {
-            $currentAttempts = (int)$_SESSION['userAttempts'];
+        if (isset($_SESSION[ 'userAttempts' ])) {
+            $currentAttempts = (int)$_SESSION[ 'userAttempts' ];
         }
 
         return (int)$currentAttempts;
@@ -167,6 +166,37 @@ public function getAttempts()
 
     // ------------------------------------------------------------------------
 
+    /**
+     * User::login
+     *
+     * @param array $account
+     */
+    public function login(array $account)
+    {
+        $_SESSION[ 'account' ] = $account;
+        unset($_SESSION[ 'userAttempts' ]);
+    }
+
+    // ------------------------------------------------------------------------
+
+    /**
+     * User::getCacheItemPool
+     *
+     * @return CacheItemPoolInterface
+     */
+    protected function getCacheItemPool()
+    {
+        $cacheItemPool = cache()->getObject('default');
+
+        if (cache()->exists('sso')) {
+            $cacheItemPool = cache()->getObject('sso');
+        }
+
+        return $cacheItemPool;
+    }
+
+    // ------------------------------------------------------------------------
+
     /**
      * User::loggedIn
      *
@@ -175,7 +205,29 @@ public function getAttempts()
      */
     public function loggedIn()
     {
-        if (isset($_SESSION['account'])) {
+        if (isset($_SESSION[ 'account' ])) {
+            return true;
+        } elseif($this->tokenOn()) {
+            return true;
+        } elseif ($this->signedOn()) {
+            return true;
+        }
+
+        return false;
+    }
+
+    // ------------------------------------------------------------------------
+
+    /**
+     * User::tokenOn
+     */
+    public function tokenOn()
+    {
+        if(false !== ($token = input()->bearerToken())) {
+            $_SESSION['account'] = (new JsonWebToken())->decode($token);
+
+            globals()->store('account', $_SESSION['account']);
+
             return true;
         }
 
@@ -185,13 +237,28 @@ public function loggedIn()
     // ------------------------------------------------------------------------
 
     /**
-     * AccessControl::login
+     * User::signedOn
      *
-     * @param array $account
+     * @return bool
+     * @throws \Psr\Cache\InvalidArgumentException
      */
-    public function login(array $account)
+    public function signOn()
     {
-        $_SESSION['account'] = $account;
+        if ($virtualUserId = input()->cookie('ssid')) {
+            $cacheItemPool = $this->getCacheItemPool();
+
+            if($cacheItemPool->hasItem('sso-' . $virtualUserId)) {
+
+                $item = $cacheItemPool->getItem('sso-' . input()->cookie('ssid'));
+                $_SESSION['account'] = $item->get();
+
+                globals()->store('account', $_SESSION['account']);
+
+                return true;
+            }
+        }
+
+        return false;
     }
 
     // ------------------------------------------------------------------------
@@ -201,8 +268,26 @@ public function login(array $account)
      */
     public function logout()
     {
-        if (isset($_SESSION['account'])) {
-            unset($_SESSION['account']);
+        $this->signOff();
+
+        if (isset($_SESSION[ 'account' ])) {
+            unset($_SESSION[ 'account' ]);
+        }
+    }
+
+    // ------------------------------------------------------------------------
+
+    /**
+     * User::signOff
+     *
+     * @throws \Psr\Cache\InvalidArgumentException
+     */
+    public function signOff()
+    {
+        if ($virtualUserId = input()->cookie('ssid')) {
+            $cacheItemPool = $this->getCacheItemPool();
+            $cacheItemPool->deleteItem('sso-' . $virtualUserId);
+            delete_cookie('ssid');
         }
     }
 }
\ No newline at end of file
diff --git a/src/Encryptions/Binary.php b/src/Encryptions/Binary.php
index d032985..294bb01 100644
--- a/src/Encryptions/Binary.php
+++ b/src/Encryptions/Binary.php
@@ -28,7 +28,6 @@ class Binary
      * @var array
      */
     private static $charactersMap = [];
-    
     /**
      * Binary::$crypt
      *
diff --git a/src/Form/Validator.php b/src/Form/Validator.php
index 17fb5d8..fee4a75 100644
--- a/src/Form/Validator.php
+++ b/src/Form/Validator.php
@@ -360,14 +360,12 @@ protected function processRules(string $field, string $label = null, $value, $ru
 
             if ( ! $callable && preg_match('/(.*?)\[(.*)\]/', $rule, $match)) {
                 $rule = $match[ 1 ];
-                if (is_array($match[ 2 ])) {
-                    $params = array_merge([$value], $match[ 2 ]);
-                } else {
-                    $params = [$value, $match[ 2 ]];
-                }
+                $params = $match[ 2 ];
             }
 
-            if (empty($params)) {
+            if ($params) {
+                $params = array_merge([$value], $params);
+            } else {
                 $params = [$value];
             }
 
@@ -386,7 +384,8 @@ protected function processRules(string $field, string $label = null, $value, $ru
                     $error = $this->customErrors[ $field ][ $rule ];
                 }
 
-                $this->errors[ $field ] = is_null($error) ? $this->getErrorMessage($rule, $field, $label, $value) : $error;
+                $this->errors[ $field ] = is_null($error) ? $this->getErrorMessage($rule, $field, $label,
+                    $params) : $error;
 
                 return false;
             }
@@ -444,11 +443,11 @@ public function getError(string $field = null): string
      * @param string      $rule
      * @param string      $field
      * @param string|null $label
-     * @param string      $value
+     * @param string      $param
      *
      * @return string
      */
-    protected function getErrorMessage(string $rule, string $field, string $label = null, string $value = null): string
+    protected function getErrorMessage(string $rule, string $field, string $label = null, string $param = null): string
     {
         // Check if custom message has been defined by user
         if (isset($this->customErrors[ $field ][ $rule ])) {
@@ -461,7 +460,7 @@ protected function getErrorMessage(string $rule, string $field, string $label =
         }
 
         $message = str_replace('{field}', $label ?? $field, $message);
-        $message = str_replace('{value}', $value ?? null, $message);
+        $message = str_replace('{param}', $this->rules[ $param ][ 'label' ] ?? $param, $message);
 
         return $message;
     }